EVTUKHOV, V. M.; VASILEVA, N. S. Conditions of oscillatory or nonoscillatory nature of solutions for a class of second-order semilinear differential equations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 4, p. 458–466, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3320. Acesso em: 6 dec. 2025.